Trenching tool

ABSTRACT

A trenching tool including a blade defining a recess opening in a first direction and a handle attached to the blade. First and second cutting elements are mounted on the blade and extend in a second direction which is opposite to the first direction.

United States Patent ,1191

Lee Jan. 1, 1974 [5 TRENCHING TOOL 285,693 9/1883 Shinabery 294/49 [76]Inventor: Mark W. Lee, 2364 Santa Ana Ave-1 Costa Mesa Cahf- 2,909,38510/1959 Meredich 294 49 [22] Filed: Aug. 31, 1972 Primary ExaminerEvonC. Blunk [2]] Appl' 285535 Assistant Examiner.lohnny D. CherryAttorney-Gordon L. Peterson [52] U.S. Cl. 294/49, 172/378 [5 l] Int. ClA01!) 1/02 57 ABSTRACT [58] Field of Search 294/49, 50.6, 5 l; I

' 7/14 30/315 172/368 378 A trenching tool mcludmg a blade definlng arecess opening in a first direction and a handle attached to [56]References Cited the blade. First and second cutting elements aremounted on the blade and extend in a second direc- 0 983 I fiL O ZPATENTS 294/4 tion which is opposite to the first direction. 9 l 8 unaan 9 1,888,170 Hornbaker 294/49 9 Claims, 6 Drawing Figures TRENCHINGTOOL BACKGROUND OF THE INVENTION It is often necessary to manually dig anarrow trench having generally vertical and parallel side walls and agenerally flat bottom. The trench may be, for example, for drainage orfor underground water distribution pipes such as pipes for a sprinklingsystem. In this latter case, it is sometimes necessary to add a lawnsprinkler system for an existing lawn in which event the trench must becut through sod. Although any manual digging operation is difficult,digging the trench through sod is particularly hard.

A conventional shovel is not at all suited for digging this kind oftrenchI-A shovel is typically too large and not of the properconfiguration to form a trench having generally vertical, parallel sidewalls and a generally flat smooth bottom. In addition, if a shovel isused to cut sod, it tends to break the sod into pieces of irregularshape which are most difficult to place back into the trench to fill thelatter after the pipe has been laid.

SUMMARY OF THE INVENTION The present invention provides a trenching toolwhich is particularly adapted for use in manually digging a narrowtrench. To this end, the trenching tool includes an elongated, narrowblade and a handle attached to the blade. The blade defines a recesswhich opens in a first direction and which is adapted to receive soiltherein.

First and second cutting elements are mounted on the blade and extendtherefrom in a second direction which is generally opposite to the firstdirection. These cutting elements serve several important functions.First, the cutting elements can be used as a sod cutter before diggingthe trench. Secondly, when the blade is inserted into the soil, thecutting elements also enter the soil and prevent twisting of the blade.This is particularly important for a narrow blade whch may tend to twistmore readily than a wider blade. Thirdly, when the cutting elements areinserted into the soil, they cut the sod behind the blade and loosen thesoil thereby facilitating the next insertion of the blade into the soil.

Each of the cutting elements can advantageously take the form of anelongated plate-like member. In this form, the cutting elements alsoserve to strengthen the blade.

The blade is relatively narrow and of approximately the same width asthe width of the desired trench. The blade includes a bottom wall andspaced parallel side walls. The side walls extend from the bottom wallin a direction opposite to the cutting elements. The side wallsfacilitate the digging of a trench having parallel vertical side walls.The blade has a point which projects axially beyond the side walls tofacilitate the initial insertion of the blade into the soil.

To further facilitate insertion of the blade, the side walls preferablytaper, and the combined width of the side walls and the plate-likemembers is of increasing height as they project toward the back end ofthe blade. The upper edges of the side walls are preferably sharpened tofacilitate lifting upwardly of the blade to remove the soil.

A pressure pad is mounted on the blade at the back end of the blade. Thepressure pad is located along the central axis of the shovel, i.e.,along the axis of the handle and the longitudinal axis of the blade. Theuser can force the blade into the ground by pushing against the pressurepad with his foot. Because the pressure pad is located along the centralaxis of the shovel, the application of a force to the pressure pad forthe purpose of insertion of the blade does not tend to twist the blade.

The plate-like members preferably are parallel to each other andsubstantially coplanar with the side walls, respectively. Thus, when theplate-like members are used as sod cutters, they cut a width of the sodwhich corresponds to the width of the blade and to the width of thetrench which is to be dug.

The blade is inherently very strong against bending loads because it isgenerally of channel shaped cross section. In addition, the plate-likemembers form strengthening webs and the bottom wall of the blade can bestrengthened by a longitudinally extending rib formed integrally withthe bottom wall. Similarly, the side walls can be strengthened by ribsformed integrally therewith. Preferably such ribs in the side wallsproject slightly outwardly to slightly widen the cut made by the bladeand reduce the drag on the side wall of the blade.

The invention can best be understood by reference to the followingdescription taken in connection with the accompanying illustrativedrawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary sideelevational view of a trenching tool constructed in accordance with theteachings of this invention.

FIG. 2 is a fragmentary front elevational view of the trenching tool.

FIG. 3 is a fragmentary top plan view of the trenching tool.

FIG. 4 is an enlarged sectional view taken generally along line 44 ofFIG. 2.

FIG. 5 is an enlarged fragmentary sectional view taken generally alongline 55 of FIG. 2.

FIG. 6 is a sectional view taken generally along line 6-6 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1-3 show a trenching tool11 which generally comprises a blade 13, an elongated handle 15, and aconnector 17 for attaching the handle to the blade. The handle 15 may beconstructed of wood or other suitable material and may be of any desiredlength and configuration. The longitudinal axes of the handle 15 and theblade 13 are aligned as viewed in front elevation (FIG. 2.)

The blade 13 is preferably constructed of a strong hard material such assteel. The blade 13 includes a pair of spaced parallel side walls 19 and21 joined by a bottom wall 23. As shown in FIG. 4, the side walls 19 and21 are generally perpendicular to the bottom wall 23. Each of the sidewalls 19 and 21 has a relatively sha'rp upper edge 25. Each of the sidewalls 19 and 21 has a tapered region 27 and a tapered region 29 (FIG. 6)to facilitate insertion of the blade 13 into the ground.

The side walls 19 and 21 are integrally joined by a web 31 which extendsat right angles to the side walls. The web 31 has a layer 33 of highfriction material such as rubber adhered thereto. The web 31 and/or thelayer 33 form a pressure pad for engagement by the foot of the user. Thepressure pad extends across the central region of the back end of theblade 13 so that application of a force thereto will not tend to pivotthe blade about its axis.

The bottom wall 23 is suitably affixed to the side walls 19 and 21 andmay be integral therewith. The bottom wall 23 has a longitudinallyextending rib 35 formed integrally therewith and extending for the fulllength of the bottom wall along the longitudinal axis of the blade 13.The rib 35 stiffens the bottom wall 23. The connector 17 may be formedintegrally with the bottom wall 23 and blends into the rib 35. Thebottom wall 23 projects axially beyond the side walls 19 and 21 at theforward end of the blade 13 to define a point 37. Although this regionof the bottom wall 23 could be of various configurations, in theembodiment illustrated, it is generally triangular in plan.

Each of the side walls 21 and 23 has a rib or dimple 39 formedintegrally therein. The ribs 39 project outwardly of the plane of theirrespective side walls 19 and 21 and extend along the tapered regions 27.

The trenching tool 11 also includes a pair of cutting elements 41 and 43which project from the bottom wall 23 in a direction opposite to thedirection in which the side walls 19 and 21 project. The cuttingelements 41 and 43 terminate in relatively sharp edges 45. Although thecutting elements 41 and 43 could be constructed in different ways, inthe embodiment illustrated, the cutting elements are plate-like and areformed integrally with the side walls 19 and 21. The cutting elements 41and 43 are of progressively increasing widths as they extend from theforward end toward the back end of the blade 13 as shown in FIG. 6. Inthe specific construction illustrated, the width of the cutting elements41 and 43 is increased by virtue of the bottom wall 23 being inclinedrelative to the edges 45 of the cutting elements 41 and 43.

In use, the blade 13 is positioned with the point 37 directed toward thesoil in which the trench is to be formed. The user then places his footon the high friction layer 33 and applies a downward force to the blade13. The high friction layer prevents slippage between the users foot andthe blade 13. Because the web 31 and the high friction layer 33 extendacross a central region of the back end of the blade 13, this force-doesnot tend to twist the blade, and accordingly the blade can be readilyforced straight into the ground.

The point 37 on the bottom wall 23 and the tapered configuration of theside walls 19 and 21 (as viewed in FIG. 1) facilitate insertion of theblade 13 into the ground. The ribs 39 adjacent the forward ends of theside walls 19 and 21 widen the cut made by the blade 13 and reducefriction between the soil and the remainder of the side walls. The sidewalls 19 and 21 and the cutting elements 41 and 43 prevent twisting ofthe blade 13 after it has been inserted into the ground. In addition,the cutting elements 41 and 43 cut and loosen the ground behind thebottom wall 23.

After the blade 13 has been inserted to the desired depth, the usermanipulates the handle to remove the soil and initiate formation of thetrench. This is preferably done by exerting a downward and rearwardforce on the handle so as to produce a prying motion and force thecutting elements 41 and 43 into the soil rearwardly of the blade.Because the side walls 19 and 21 are perpendicular to the bottom wall 23and parallel, the sides of the resulting trench will be substantiallyvertical. The second insertion of the blade 13 into the ground and itssubsequent manipulation is facilitated by the action of the cuttingelements 41 and 43 during the immediately prior insertion andmanipulation of the blade. This is particularly advantageous when thetrenching tool 11 is used for cutting a trench in sod. If desired, thecutting elements 41 and 43 with their sharp edges 45 can be run over thedesired path of the trench to cut the sod.

The blade 13 is very strong because of its channelshaped configuration.The web 31, the ribs 35 and 39, and the connector 17 also serve tostrengthen the blade 13.

Although an exemplary embodiment of the invention has been shown anddescribed, many changes, modifications and substitutions may be made byone having ordinary skill in the art without necessarily departing fromthe spirit and scope of this invention.

I claim:

1. A trenching tool comprising:

a blade having an edge adapted to penetrate soil, said blade defining arecess opening in a first direction and adapted to receive soil therein,said blade having a forward end and a back end;

an elongated handle;

means for attaching the handle to the blade to facilitate manualmanipulation of the blade;

first and second cutting elements mounted on said blade and extendingtherefrom in a second direction, said second direction being generallyopposite said first direction;

said cutting elements being spaced apart, each of said cutting elementsterminating in a cutting edge adapted to penetrate soil;

said first and second cutting elements including first and secondplate-like members, respectively, said blade having substantiallyparallel side edges, said first and second plate-like members beingattached to and extending substantially along said side edges,respectively, whereby said first and second plate-like members aregenerally parallel;

said blade including first and second side walls joined by a bottomwall, said side walls being generally parallel to each other and to saidplate-like members, said side walls defining said side edges,respectively; and

said first and second side walls being substantially coplanar with saidfirst and second plate-like members, respectively, said side walls andsaid first and second plate-like members projecting in oppositedirections from said bottom wall, each of said plate-like membersextending a greater distance from said bottom wall near the back end ofthe blade then near the front end of the blade.

2. A trenching tool as defined in claim 1 wherein said bottom wallprojects from said side walls at said front end of the blade andterminates in a relatively sharp soil penetrating point and saidtrenching tool includes a pressure pad adjacent the back end of theblade and located centrally with respect to the longitudinal axis of theblade.

3. A trenching tool as defined in claim 2 including first and secondribs in said first and second side walls, respectively, adjacent theforward ends of the side walls, and a longitudinally extending ribformed integrally in said bottom wall and extending longitudinally ofthe blade along a central region of the bottom wall.

4. A trenching tool as defined in claim 3 wherein the combined height ofthe plate-like members and the side walls is of less height near thefront end of the blade than near the back end of the blade.

5. A trenching tool comprising:

a blade having an edge adapted to penetrate soil, said blade defining arecess opening in a first direction and adapted to receive soil therein,said blade having a forward end and a back end;

an elongated handle;

means for attaching the handle to the blade to facilitate manualmanipulation of the blade;

first and second cutting elements mounted on said blade and extendingtherefrom in a second direction, said second direction being generallyopposite said first direction;

said cutting elements being spaced apart, each of said cutting elementsterminating in a cutting edge adapted to penetrate soil; and

said blade being elongated and including a pair of generally parallelside walls and a bottom wall joining said side walls, said side walls atleast partially defining said recess, said side walls and said cuttingelements extending in generally opposite directions.

6. A trenching tool comprising:

a blade having an edge adapted to penetrate soil, said blade defining arecess opening in a first direction and adapted to receive soil therein,said blade having a forward end and a back end;

an elongated handle;

means for attaching the handle to the blade to facilitate manualmanipulation of the blade;

first and second plate-like cutting elements mounted on said blade andextending therefrom in a second direction, said second direction beinggenerally opposite said first direction;

said cutting elements being spaced apart, each of said cutting elementsterminating in a cutting edge adapted to penetrade soil; and

said cutting edges extending generally in the direction from the forwardend to the back end of the blade.

7. A trenching tool as defined in claim 6 wherein said blade includes abottom wall and first and second parallel side walls projecting fromsaid bottom wall, said side walls being perpendicular to said bottomwall.

8. A trenching tool as defined in claim 7 wherein the first and secondplate-like cutting elements are substantially coplanar with said firstand second side walls, respectively.

9. A trenching tool as defined in claim 6 including a pressure padacross the central region of the back end of the blade to permit theblade to be inserted into the soil under pressure of the users foot.

1. A trenching tool comprising: a blade having an edge adapted topenetrate soil, said blade defining a recess opening in a firstdirection and adapted to receive soil therein, said blade having aforward end and a back end; an elongated handle; means for attaching thehandle to the blade to facilitate manual manipulAtion of the blade;first and second cutting elements mounted on said blade and extendingtherefrom in a second direction, said second direction being generallyopposite said first direction; said cutting elements being spaced apart,each of said cutting elements terminating in a cutting edge adapted topenetrate soil; said first and second cutting elements including firstand second plate-like members, respectively, said blade havingsubstantially parallel side edges, said first and second platelikemembers being attached to and extending substantially along said sideedges, respectively, whereby said first and second plate-like membersare generally parallel; said blade including first and second side wallsjoined by a bottom wall, said side walls being generally parallel toeach other and to said plate-like members, said side walls defining saidside edges, respectively; and said first and second side walls beingsubstantially coplanar with said first and second plate-like members,respectively, said side walls and said first and second plate-likemembers projecting in opposite directions from said bottom wall, each ofsaid plate-like members extending a greater distance from said bottomwall near the back end of the blade than near the front end of theblade.
 2. A trenching tool as defined in claim 1 wherein said bottomwall projects from said side walls at said front end of the blade andterminates in a relatively sharp soil penetrating point and saidtrenching tool includes a pressure pad adjacent the back end of theblade and located centrally with respect to the longitudinal axis of theblade.
 3. A trenching tool as defined in claim 2 including first andsecond ribs in said first and second side walls, respectively, adjacentthe forward ends of the side walls, and a longitudinally extending ribformed integrally in said bottom wall and extending longitudinally ofthe blade along a central region of the bottom wall.
 4. A trenching toolas defined in claim 3 wherein the combined height of the plate-likemembers and the side walls is of less height near the front end of theblade than near the back end of the blade.
 5. A trenching toolcomprising: a blade having an edge adapted to penetrate soil, said bladedefining a recess opening in a first direction and adapted to receivesoil therein, said blade having a forward end and a back end; anelongated handle; means for attaching the handle to the blade tofacilitate manual manipulation of the blade; first and second cuttingelements mounted on said blade and extending therefrom in a seconddirection, said second direction being generally opposite said firstdirection; said cutting elements being spaced apart, each of saidcutting elements terminating in a cutting edge adapted to penetratesoil; and said blade being elongated and including a pair of generallyparallel side walls and a bottom wall joining said side walls, said sidewalls at least partially defining said recess, said side walls and saidcutting elements extending in generally opposite directions.
 6. Atrenching tool comprising: a blade having an edge adapted to penetratesoil, said blade defining a recess opening in a first direction andadapted to receive soil therein, said blade having a forward end and aback end; an elongated handle; means for attaching the handle to theblade to facilitate manual manipulation of the blade; first and secondplate-like cutting elements mounted on said blade and extendingtherefrom in a second direction, said second direction being generallyopposite said first direction; said cutting elements being spaced apart,each of said cutting elements terminating in a cutting edge adapted topenetrade soil; and said cutting edges extending generally in thedirection from the forward end to the back end of the blade.
 7. Atrenching tool as defined in claim 6 wherein said blade includes abottom wall and first and secoNd parallel side walls projecting fromsaid bottom wall, said side walls being perpendicular to said bottomwall.
 8. A trenching tool as defined in claim 7 wherein the first andsecond plate-like cutting elements are substantially coplanar with saidfirst and second side walls, respectively.
 9. A trenching tool asdefined in claim 6 including a pressure pad across the central region ofthe back end of the blade to permit the blade to be inserted into thesoil under pressure of the user''s foot.